Several other students on the bus at the time were not aware of the incident, police said.

Authorities said Das did pass a background check before he was hired and did not have a prior criminal record.

Although there are currently no other reported victims, police said they are worried there could be others.

"At this time we have no evidence that there are any other victims, but whenever an offense like this occurs, we do want to make the public aware of the individual who’s been arrested," said Lucille Baur of the Montgomery County Police Department.

Dr. Barbara Haughey, the principal at Ashburton Elementary School, issued the following statement:

"We are deeply distressed about this incident … I want to assure you that every appropriate action has been taken to support the student and the family."